Mackenzie “Mac” Allen (Geena Davis), the 45-year old Independent Vice President, is about to enter a world in which no woman has ever stepped foot in before. While in attendance at a ceremony with her husband, Chief of Staff Rod Calloway (Kyle Secor), Mackenzie is given the startling news that President Bridges needs emergency brain surgery to treat a brain tumor. Mackenzie is given an additional shock when she is also informed that in the event the President doesn’t make it through surgery, the party doesn’t want her succeed him.

However, despite sexist insults from both the dying President and Speaker of the House Nathan Templeton (Donald Sutherland), Mackenzie decides to fulfill her duty as Presidential successor and take her rightful place as Commander in Chief of the United States of America.

When a longtime outspoken critic of the Equal Rights Amendment passes away and his wife prepares to take over his Congressional seat, Mac sees the opportunity to amend the Constitution and finally pass the ERA. Meanwhile, she prepares to participate in a previously scheduled Get Out the Vote event with Templeton, which turns into more of a presidential debate. On the home front, Rod is approached about doing a story on his relationship with Mac a Presidential marriage and it turns out Kelly has a past with the writer. Rebecca continues her relationship with her IM buddy, but theyre each shocked at the others identity when they meet in person. And the differences between Mac and Dickies beliefs become glaringly apparent.